1. Field of the Invention
The present invention relates generally to endoscopes, and in particular the configuration of a handle used for a multifunction endoscope.
2. Description of Related Art
An endoscope is an illuminated medical device used look inside the body and examine organs. An endoscope can be rigid or flexible. Endoscopes designed for particular procedures often have specialized names, such as cystoscope (urethra, bladder), nephroscope (kidney), bronchoscope (bronchi), laryngoscope (larynx), otoscope (ear), arthroscope (joint) and laparoscope (abdomen). In addition to being used for viewing and examination, endoscopes are often used with various types of medical instruments for diagnostic and therapeutic procedures. An example of these medical instruments includes a medical laser device using fiber optics to deliver the laser energy to, typically, the distal end of the endoscope. Other medical instruments that can be used with endoscopes include grasping, cutting, tissue sampling and suturing medical instruments as well as medical instruments designed to provide energy other than laser energy such as RE and ultrasonic energy.
Endoscopic removal of tissue by means of lasers has been realized in procedures such as photoselective vaporization of prostate (PVP) for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). Lasers in the visible and invisible spectral range have been utilized for endoscopic procedure of tissue removal. Tissue removal is typically carried out under endoscopic visualization of the operating field through a telescope. Laser light is guided to the operating field by an optical light guide (laser fiber). To steer the light guide to the target tissue an endoscope is often utilized. In some implementations the telescope can be embodied in the endoscope as a fixed or modular component. Also, such procedures rely on a supply of irrigating fluid to the operating region, to remove debris, cool tissue and otherwise cooperate with the activity.
Performing a surgical laser procedure through an endoscope creates several challenges. Vaporization of tissue in a body cavity filled with an irrigant can create vapor bubbles and tissue particles that get released into the irrigant and that can obscure the view of the surgeon.
Controlling the surgical effect the laser has on tissue requires the surgeon to position the laser fiber with high precision. The surgeon has to consider the characteristics of the laser beam such as its divergence coming out of the laser fiber and control the distance between laser fiber and tissue to achieve the desired effect. In some instances the laser effect can change its nature dependent on the distance between laser fiber and tissue. In some cases vaporization will occur when the fiber is close to tissue but coagulation without vaporization will occur when the fiber is further away from tissue.
The surgeon has to control the position of the distal tip of the laser fiber relative the distal tip of the endoscope to avoid damage to the endoscope by unintentional exposure of the endoscope to laser light.
Thus, in some high power laser applications, it is possible to damage an endoscope by inadvertently directing laser radiation into the structure. In addition, it is necessary to provide for an effective irrigation flow in such systems. Finally, is desirable to provide a structural design, which is comfortable to hold and utilize by surgeons. An endoscope is described herein that allows surgeons to safely and effectively perform laser surgery, including transurethral laser vaporization of prostate tissue.